High power fiber lasers are being developed for applications such as industrial laser materials processing (e.g., metal cutting and welding) and military directed-energy and laser radar systems. IPG Photonics, Inc. (Oxford, Mass.), for example, has produced a 10-kW-cw-power YLS-10,000-SM fiber laser based on ytterbium-doped silica fibers operating around 1070 nm. See U.S. Pat. Nos. 7,593,435 and 7,848,368 incorporated herein by this reference.
There is concern, however, that such high-power lasers, operating at wavelengths less than about 1400 nm, can cause eye damage to personnel subject to stray power from lasers, since even a small fraction of the power can be focused onto and cause damage to the retina.